Things You Should Know about Filling a Prescription

Filling a prescription is crucial for those who need glasses; therefore, to know something about prescription filling is necessary.

1. You need professional medical optometry.

The first step of filling a prescription is to have a medical optometry, which is conducted by an optometrist in two steps according to the related medical theories. The first step is to have a comprehensive examination which aims to exclude the eye diseases except ametropia. The second step is to measure the refractive state and visual functions accurately from both subjective and objective perspectives on the basis of the result of the first step which is normal.

For medical optometry, the diopter will not be determined just on the basis of the result of medical optometry, but will be on the comprehensive factors include age, the position of the eyes, the adjustment ability of the eyes, the coordination function of eyes, the influence of diseases on the refraction etc. And a regular eye re-examination, which is to adjust the degree of glasses timely or to decide if the glasses is appropriate to wear or not, is also necessary and should be done under the process of optometry.

2. Glasses are for vision correction.

The most common way for vision correction is to wear a pair of appropriate glasses. For myopia sufferers, a clear vision could be obtained by wearing prescription glasses, and in this way, the vision is corrected. But some myopia suffers prefer a blurry vision to a pair of glasses, for they are afraid that their vision would become worse and can never get rid of them once they begin to wear glasses. Actually, worse vision has nothing to do with glasses.

Yes, there are teenagers whose vision become worse after wearing glasses for a while. This is the result of heavy load on the growing eyeballs. Some people still ignore the hygiene of eyes even after wearing glasses and bad habits of reading, like long-time reading, lying down while reading, or reading under dim light etc, can also lead to vision worsening. And there are people who regard glasses wearing as a kind of burden and thus keep taking off and putting on glasses all the time, which makes their eyes always in an unstable adjustment state. In this case, worsening vision is inevitable.

3. Mydriasis test optometry is important for teenagers.

Mydriasis test optometry is also called objective optometry. It is the optometry conducted under the condition of mydriasis and the state of completely paralyzed ciliary muscle by using certain drug. In this way, the influence and interference of eyes’ regulation and the possibility of pseudomyopia could be removed, and the accurate refractive status test could be ensured. After some time of the mydriasis test optometry, one needs to go check if the glasses made on the basis of the medical optometry result has ever cause any unusual discomfort such as dizziness, nausea, blurry vision, deformed vision or losing the ability of walking stably and so on. In this way, the objective result of mydriasis test optometry and the subjective result of this check are combined together, thus enables the best effect for the vision correction.

Some people are not willing to have mydriasis test optometry for fear of discomfort of eyes after it and inability of seeing things in front of them clearly. In fact, there is no need to worry for the effect of the drug is temporary and after some time, this effect will disappear as long as no such drug is used again. If one refuses to have mydriasis test optometry, there would have some deviation of the result due to the adjustment of ciliary muscle and crystalline lens. Therefore, mydriasis test optometry is a curial process for filling a prescription.

CR-39 began the change of optical lenses from glass to plastic materials. It is
lighter weight, more impact resistant than glass lenses; thus, becoming a popular
type of material used in single vision, bifocal, and multifocal or progressive lenses.

Material is low price and easy to manufacture. It is often preferred by individuals
on a tight budget. However, because of its 1.50 index, customers with high prescription
powers are recommended to use higher index lenses such as 1.56, PC, 1.67, or 1.74
lenses.

CR39 Lenses Features are:

Fragmentation: When plastic lens breaks, it breaks into larger
fragments than their glass counterparts. Furthermore, the fragmented pieces are
not as sharp as glass.

Fogging: CR39 lenses are less likely to fog-up than glass
lenses because it responds more favorably to temperature changes.

Weight: Glass lenses are approximately 2X heavier than plastic
lenses of similar size and shape. The lighter weight provides the wearer greater
comfort.

Tinting: CR39 lenses are great for tinting. Lenses can be
tinted to virtually any color. Even lenses with variable thickness are able to be
tinted evenly.

If you want thinner, lighter lenses, and have an milder prescription, then mid index
lenses are the way to go. As prescription increases, the lenses become thicker.
Thicker lenses increase internal reflections that reduce vision quality. Furthermore,
thicker lenses add to the weight of each pair of glasses reducing comfort. Mid-Index
lenses refract the light at a greater angle allowing the wearer to have a beautifully
thin and light pair of glasses.

Mid Index Lenses Features are:

Fragmentation: When plastic lens breaks, it breaks into larger
fragments than their glass counterparts. Furthermore, the fragmented pieces are
not as sharp as glass.

Fogging: Mid Index lenses are less likely to fog-up than glass
lenses because it responds more favorably to temperature changes.

Weight: Glass lenses are approximately 2X heavier than plastic
lenses of similar size and shape. The lighter weight provides the wearer greater
comfort.

Tinting: Mid index lenses are also tintable, so you can get
that pair of sunglasses you’ve been eyeing for so long.

Polycarbonate lenses has a high index of refraction 1.59 and low density making
PC lenses 20% thinner and 25% lighter than regular plastic lenses. Polycarbonate
lenses are the most impact resistant lenses on the market. Therefore, it is the
industry standard for safety goggles, and highly recommended for kids' lenses.

Polycarbonate Lenses Features are:

Impact Resistant: Polycarbonate material was originally made
for uses on canopies covering fighter planes and then made its way into space on
astronaut visors and space shuttle windshields. Today it is readily available to
the public. It impact resistance makes the material extremely suitable for sports,
industrial safety goggles, and children's eyewear.

Scratching: The reason for polycarbonate lenses' impact resistance
is because of its "softness". Softer materials will flex instead of fragment when
met with great force. However, the property allows lenses to be scratched easily.
Therefore, every single one of our polycarbonate lenses is multi-coated with hard
coating that forms a protective layer around the lenses allowing the lenses to be
free from scratches while retaining its impact resistant qualities.

UV Protection: Polycarbonate lenses inherently carries UV
protection properties that blocks nearly 100% of the UV rays from entering the back
of the retina.

If you want thinner, lighter lenses, then high index lenses are the way to go. As
prescription increases, the lenses become thicker. Thicker lenses increase internal
reflections that reduce vision quality. Furthermore, thicker lenses add to the weight
of each pair of glasses reducing comfort. Hi-Index lenses refract the light at a
greater angle allowing the wearer to have a beautifully thin and light pair of glasses.

High Index Lenses Features are:

Fragmentation: When plastic lens breaks, it breaks into larger
fragments than their glass counterparts. Furthermore, the fragmented pieces are
not as sharp as glass.

Fogging: High Index lenses are less likely to fog-up than
glass lenses because it responds more favorably to temperature changes.

Weight: Glass lenses are approximately 2X heavier than plastic
lenses of similar size and shape. The lighter weight provides the wearer greater
comfort.

Reflections: High Index lenses have much lower internal reflection
and surface glare than glass materials.

Tinting: High index lenses are also tintable, so you can get
that pair of sunglasses you've been eyeing for so long.